The population of the United States, as in most developed nations, is aging and is doing so at an increasing rate. This change in demographics is having a dramatic effect on the nation's healthcare delivery system and the related public costs. The Congressional Budget Office predicts that the cost of long-term care for the elderly will reach $207 billion in 2020 and $346 billion in 2040. By 2030, spending for Social Security, Medicare and Medicaid will amount to almost 60% of the federal budget. The strong predilection of most of the elderly, and their families, is to prefer long-term care delivery in the home rather than in the institutionalized setting. This has resulted in a massive shift of elderly care costs t unpaid family caregivers, and this cost is not reflected in the budget numbers provided above. However, the continuation of this shifting of elderly care costs to family members is not sustainable due to the decrease in birth rate and the increasing number of adults surviving to old age without living children. As a result there will be an increasingly urgent need for publicly funded support of elderly home-based care while, at the same time, an equally urgent need to control the spirally cost of this care. More efficient delivery of home-care services for the eldery can have a significant impact on controlling, or even reducing, the cost of long-term elderly care. However, in order to deliver this care cost-effectively, a technology-based infrastructure optimized for this purpose will be required. One means of achieving this goal is by developing innovative mobile technology solutions which can monitor and maintain the activity, health and safety, and thereby the independence, of the elderly within the home. Our working hypothesis in this proposal is that a properly designed, head-mounted, wearable-computing solution can bring unique and powerful capabilities to address the need for more effective and lower-cost elderly home monitoring. We propose to develop a highly compact, light-weight, innovative technology called the Head-mounted Activity Monitoring (HAM) System.